A method and apparatus for detecting a cover opening of an image forming apparatus and a method and apparatus for controlling the supply of power to the image forming apparatus by detecting cover opening are provided. A detection is made as to whether first and second covers for the image forming apparatus are both closed. A verification is made as to whether memory information of a predetermined memory placed in the first cover is detected, if at least any one of the first and second covers is open. A determination is made that the second cover is open, if the memory information is detected. Accordingly, a user can know which cover is open among covers provided in the image forming apparatus by using one switching element. In addition, since a circuit used for detecting cover opening can be implemented with low cost, maintenance of the circuit can be promptly carried out.